/* roulang page: index */
:root {
      --primary: #1A3A5C;
      --primary-deep: #0F2840;
      --accent: #D4A843;
      --accent-hover: #C49635;
      --bg-light: #F7F9FC;
      --bg-blue: #E8F0F8;
      --white: #FFFFFF;
      --text-main: #1E2A38;
      --text-muted: #5A6B7D;
      --text-footer: #8A9BB0;
      --border: #E5EAF0;
      --shadow-card: 0 2px 16px rgba(26,58,92,0.08);
      --shadow-hover: 0 8px 28px rgba(26,58,92,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-title: 'Noto Sans SC', sans-serif;
      --font-body: 'Inter', 'Noto Sans SC', sans-serif;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: var(--white);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
    }
    
    /* 导航 */
    .header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(8px);
      height: 72px;
      border-bottom: 1px solid var(--border);
      display: flex;
      align-items: center;
      transition: box-shadow 0.2s;
    }
    .header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: 0.5px;
      white-space: nowrap;
    }
    .logo-icon {
      width: 36px;
      height: 36px;
      background: var(--primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent);
      font-size: 20px;
      font-weight: 700;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-muted);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
      font-size: 0.95rem;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      border-bottom-color: var(--accent);
    }
    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 10px 24px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border-bottom: none !important;
      transition: background 0.2s, box-shadow 0.2s;
    }
    .nav-cta:hover {
      background: var(--primary-deep);
      box-shadow: 0 4px 18px rgba(26,58,92,0.25);
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary);
      cursor: pointer;
      line-height: 1;
    }
    
    /* 板块基础 */
    section {
      padding: 120px 0;
    }
    .section-title {
      font-family: var(--font-title);
      font-size: 2.25rem;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 640px;
      margin: 0 auto 56px;
      font-size: 1.1rem;
    }
    
    /* Hero */
    #hero {
      background: var(--bg-light);
      padding: 0;
      min-height: 90vh;
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-content h1 {
      font-family: var(--font-title);
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.25;
      color: var(--primary);
      margin-bottom: 24px;
    }
    .hero-content p {
      font-size: 1.15rem;
      color: var(--text-muted);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      transition: all 0.2s ease;
      text-align: center;
      font-size: 1rem;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
    }
    .btn-primary:hover {
      background: var(--primary-deep);
      box-shadow: 0 4px 20px rgba(26,58,92,0.25);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: var(--bg-blue);
    }
    .btn-accent {
      background: var(--accent);
      color: var(--primary);
      border: none;
      font-weight: 700;
    }
    .btn-accent:hover {
      background: var(--accent-hover);
    }
    .hero-image {
      background: #d9dfe6;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: var(--shadow-card);
      aspect-ratio: 4/3;
    }
    .hero-image img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    
    /* 问题区 */
    #problem {
      background: var(--bg-blue);
    }
    .problem-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 40px;
    }
    .problem-card {
      background: var(--white);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      display: flex;
      gap: 20px;
      align-items: flex-start;
      border: 1px solid var(--border);
    }
    .problem-icon {
      font-size: 2rem;
      color: var(--accent);
      line-height: 1;
    }
    .problem-card h3 {
      font-family: var(--font-title);
      font-weight: 600;
      font-size: 1.25rem;
      margin-bottom: 8px;
      color: var(--primary);
    }
    .problem-card p {
      color: var(--text-muted);
      font-size: 0.95rem;
    }
    
    /* 解决方案 非对称 */
    #solution .solution-row {
      display: grid;
      grid-template-columns: 7fr 5fr;
      gap: 32px;
      margin-bottom: 32px;
    }
    #solution .solution-row.reverse {
      grid-template-columns: 5fr 7fr;
    }
    .solution-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 36px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border);
      display: flex;
      flex-direction: column;
      transition: 0.2s;
    }
    .solution-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-2px);
    }
    .solution-icon {
      width: 64px;
      height: 64px;
      background: var(--bg-blue);
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
    }
    .solution-icon img {
      width: 36px;
      height: 36px;
    }
    .solution-card h3 {
      font-family: var(--font-title);
      font-size: 1.4rem;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--primary);
    }
    .solution-card p {
      color: var(--text-muted);
      margin-bottom: 24px;
      flex: 1;
    }
    .text-link {
      color: var(--primary);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    
    /* 成果区 */
    #results {
      background: var(--white);
    }
    .results-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .stats-col {
      display: flex;
      flex-direction: column;
      gap: 40px;
    }
    .stat-item {
      border-left: 4px solid var(--accent);
      padding-left: 24px;
    }
    .stat-number {
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }
    .stat-unit {
      font-size: 1.25rem;
      font-weight: 500;
      color: var(--text-muted);
    }
    .stat-desc {
      color: var(--text-muted);
      margin-top: 8px;
    }
    .results-image img {
      border-radius: 16px;
      box-shadow: var(--shadow-card);
    }
    
    /* 证言 */
    #testimonials {
      background: var(--bg-light);
    }
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .testimonial-card {
      background: var(--white);
      padding: 32px;
      border-radius: var(--radius-card);
      border-left: 4px solid var(--accent);
      box-shadow: var(--shadow-card);
    }
    .testimonial-text {
      font-style: italic;
      color: var(--text-main);
      margin-bottom: 24px;
      font-size: 1rem;
      line-height: 1.7;
    }
    .testimonial-author {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .author-avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #d9dfe6;
    }
    .author-info h4 {
      font-weight: 600;
      font-size: 0.95rem;
    }
    .author-info span {
      color: var(--text-muted);
      font-size: 0.8rem;
    }
    
    /* FAQ */
    #faq {
      background: var(--white);
    }
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    details {
      background: var(--white);
      border: 1px solid var(--border);
      border-radius: var(--radius-card);
      margin-bottom: 16px;
      padding: 20px 24px;
      transition: 0.2s;
    }
    details[open] {
      background: var(--bg-light);
    }
    summary {
      font-weight: 600;
      font-size: 1.1rem;
      cursor: pointer;
      list-style: none;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--primary);
    }
    summary::-webkit-details-marker {
      display: none;
    }
    .faq-answer {
      margin-top: 16px;
      color: var(--text-muted);
      line-height: 1.7;
    }
    
    /* CTA */
    #cta {
      background: var(--primary);
      text-align: center;
      padding: 100px 0;
      position: relative;
      overflow: hidden;
    }
    #cta::before {
      content: "";
      position: absolute;
      top: -100px;
      left: -100px;
      width: 300px;
      height: 300px;
      background: rgba(255,255,255,0.05);
      border-radius: 50%;
      filter: blur(60px);
    }
    #cta h2 {
      color: white;
      font-size: 2.5rem;
      font-weight: 600;
    }
    #cta p {
      color: rgba(255,255,255,0.7);
      margin: 20px 0 36px;
    }
    
    /* Footer */
    .footer {
      background: var(--primary-deep);
      color: var(--text-footer);
      padding: 64px 0 32px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 48px;
    }
    .footer-logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 1.3rem;
      color: white;
      margin-bottom: 12px;
    }
    .footer a {
      color: var(--text-footer);
      transition: 0.2s;
    }
    .footer a:hover {
      color: white;
    }
    .footer-links {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      text-align: center;
      font-size: 0.9rem;
    }
    
    @media (max-width: 1024px) {
      .hero-grid, .results-grid {
        gap: 40px;
      }
      .hero-content h1 {
        font-size: 2.4rem;
      }
    }
    
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 24px;
        box-shadow: 0 20px 30px rgba(0,0,0,0.1);
        gap: 20px;
      }
      .nav-links.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-content p {
        margin-left: auto;
        margin-right: auto;
      }
      .btn-group {
        justify-content: center;
      }
      .problem-grid {
        grid-template-columns: 1fr;
      }
      #solution .solution-row,
      #solution .solution-row.reverse {
        grid-template-columns: 1fr;
      }
      .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .results-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    
    @media (max-width: 480px) {
      .hero-content h1 {
        font-size: 2rem;
      }
      section {
        padding: 80px 0;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }